private void help() throws IOException {
String[] help =
new String[] {
help_fw_page, help_bw_page, help_fw_dline, help_bw_dline, help_fw_sline, help_bw_sline,
help_go_start, help_go_end, help_fw_search1, help_fw_search2, help_bw_search1,
help_bw_search2,
help_help, help_quit
};
// Remember the 'current' buffer so that we can repaint it
// when we are done.
ScreenBuffer prevBuffer = this.currentBuffer;
// Prepare and paint the help screen
ScreenBuffer buffer = new ScreenBuffer(true);
for (int i = 0; i < help.length; i++) {
prepareLine(help[i], i, buffer);
}
buffer.adjust(0, 0);
buffer.output();
prompt(str_any_key);
// Wait till the user is done, then repaint the previous screen.
pr.read();
prompt();
prevBuffer.output();
}
/**
* Prepare lines for output by painting them to our private buffer starting at the supplied
* bufferLineOffset
*
* @param line the line to be prepared
* @param lineNo the line's line number
* @param buffer the ScreenBuffer we are preparing
*/
private boolean prepareLine(String line, int lineNo, ScreenBuffer buffer) {
buffer.startLine(lineNo);
int pos = 0;
int len = line.length();
int startMatchPos = len;
int endMatchPos = len;
if (matcher != null) {
matcher.reset(line);
if (matcher.find(0)) {
startMatchPos = matcher.start();
endMatchPos = matcher.end();
}
}
for (int i = 0; i < len; i++) {
if (i == startMatchPos) {
buffer.setColor(MATCH_COLOR);
} else if (i == endMatchPos) {
if (matcher.find(i)) {
startMatchPos = matcher.start();
endMatchPos = matcher.end();
if (startMatchPos > i) {
buffer.setColor(DEFAULT_COLOR);
}
} else {
buffer.setColor(DEFAULT_COLOR);
}
}
// FIXME - support different renderings, including ones where
// control characters are rendered as visible characters?
char ch = line.charAt(i);
switch (ch) {
case '\n':
throw new AssertionError("no newlines expected");
case '\r':
// ignore bare CRs.
break;
case '\t':
int fill = tabSize - pos % pageWidth % tabSize;
for (int j = 0; j < fill; j++) {
buffer.putChar(' ');
}
pos += fill;
break;
default:
if (ch >= ' ' && ch <= '\377' && ch != '\177') {
buffer.putChar(ch);
} else {
buffer.putChar('?');
}
pos++;
}
}
buffer.setColor(DEFAULT_COLOR);
buffer.endLine();
return !buffer.isComplete();
}
/**
* Prepare lines for output by painting them to our private buffer in the reverse direction
* starting at a given end line number and (rendered) subline number.
*/
private ScreenBuffer prepareReverse(int endLineNo, int endSublineNo) {
ScreenBuffer buffer = new ScreenBuffer(false);
int lineNo = endLineNo;
String line = null;
boolean more = true;
while (more && lineNo >= 0) {
line = lineStore.getLine(lineNo);
more = prepareLine(line, lineNo, buffer);
lineNo--;
}
if (buffer.adjust(endLineNo, endSublineNo)) {
return buffer;
} else {
return prepare(0, 0);
}
}
/**
* Prepare lines for output by painting them to our private buffer in the forward direction
* starting at a given line number and (rendered) subline number.
*
* @param startLineNo
*/
private ScreenBuffer prepare(int startLineNo, int startSublineNo) {
while (true) {
ScreenBuffer buffer = new ScreenBuffer(true);
int lineNo = startLineNo;
boolean more;
do {
String line = lineStore.getLine(lineNo);
if (line == null) {
break;
}
more = prepareLine(line, lineNo, buffer);
lineNo++;
} while (more);
if (buffer.adjust(startLineNo, startSublineNo) || startLineNo == 0) {
return buffer;
} else {
startLineNo -= 1;
startSublineNo = LAST_SUBLINE;
}
}
}
